Brain structural changes in essential tremor: voxel-based morphometry at 3-Tesla.

BACKGROUND

Abnormalities in cerebello-thalamo-cortical pathways have been suggested as a basis for essential tremor (ET). Two voxel-based morphometry (VBM) studies, each using a 1.5-T magnet, evaluated ET patients, leading to contradictory results. Using a 3-T magnet, we assessed whether white or gray matter changes occurred in ET patients vs. controls.

METHODS

We recruited 19 ET patients (mean age 69.8+/-9.4 years) and 20 age and gender-matched controls. 3-T MRI data were analyzed using the Statistical Parametric Mapping (SPM) 5 package.

RESULTS

In case-control comparisons, white matter changes were seen in several areas (right cerebellum, left medulla, right parietal lobe, and right limbic lobe); gray matter changes were seen in several areas as well (bilateral cerebellum, bilateral parietal lobes, right frontal lobe, and right insula) (p<0.001, uncorrected at a voxel level). Compared with controls, ET patients with severe tremor had white matter changes in the midbrain, both occipital lobes, and right frontal lobe, and gray matter changes bilaterally in the cerebellum (p<0.001, uncorrected at a voxel level).

CONCLUSIONS

Structural white and gray abnormalities may be detected in ET patients using VBM and a high-field MRI scanner. Such changes may be related to the pathological substrates associated with this disease.